Reciprocating pump

ABSTRACT

A reciprocating pump for liquids and adapted to quick conversion to double its pumping capacity with the addition of extra pumping cylinders. A rotary crankshaft operates through crossheads to drive pistons in the pumping cylinders, and a piston rod rigidly, but releasably, connects each piston and crosshead. Flexible bellows seal between each crosshead guide and piston rod to prevent loss of oil from the case around the piston rod to prevent any of the liquid pumped or outside dirt from reaching the case. The bellows also aid in the circulation of oil from the case to and around each crosshead and associated parts.

. United States Patent 1191 1111 3,817,663 Zehner June 18, 1974 RECIPROCATING PUMP 3,118,389 1/1964 Camp 74/1s.2 3,299,828 1/1967 Josephian 417/569 [75] Inventor Zehm" Ashland 3,314,337 4/1967 Payne et a1. 92/157 73 Assignee; Tecno products Company, 3,364,871 1/ 1968 Wilson 417/539 X Mansfield, Ohio Primary Examiner-C. .1. Husar [22] Flled' 1971 Assistant ExaminerLenard Smith [21] App]. No.: 198,667 Attorney, Agent, or Firm-Oldham & Oldham [52] 11.8. C1 417/569, 92/160, 92/259, ABSTRACT 417/ 454 A reciprocating pump for liquids and adapted to quick [51] Int. Cl. F0lb 31/10, F04b 21/02 conversion t d bl its pumping capacity with the Fleld of Search 256, 259, 153, addition of extra pumping cylinder5 A rotary crank- 92/ 157, 160; 4l7/454, 5 shaft operates through crossheads to drive pistons in the pumping cylinders, and a piston rod rigidly, but References Clted releasably, connects each piston and crosshead. Flexi- UNITED STATES PATENTS -ble bellows seal between each crosshead guide and 1,275,697 8/1918 Joyce 137/540 x P rod to prevent 1058 Of Oil e case around 1,450,135 3/1923 Clarlc 417/569 the plston rod to p nt any f th hquld pumped or 1,599,716 9/ 1926 Replogle 417/569 X outside dirt from reaching the case. The bellows also 2,005,299 6/1935, Denrod 417/554 aid in the circulation of oil from the case to and 2,102,797 Helmer around each crossh ad and associated parts 2,331,070 10/1943 Farque 417/454 X 3,045,606 7/ 1962 Schmidt 417/569 X 391311118, 6 Drawing Figures Ill.

46 34 2B H 6 32 5a 098 94 10 46 2s 1s 2s 66 5 i v 8 6 1 22 I8 14 22 V1 58 a2 IO 4 106 46 20 58 T PT 6 6 7 a 70. 6 l l G 40 3 40 4 58 74 7 7 RECIPROCATING PUMP BACKGROUND Various receiprocating pumps have been proposed heretofore. But, most of these have not included replaceable crosshead sleeves interposed between the crankshaft and the pumping cylinders. Crossheads, as in the present invention, improve operating life, and when provision is made for improved lubrication of the crossheads and associated parts, the complete pump assembly is particularly long lived and trouble free. Also, in known reciprocating pumps for liquids, dirt or liquid pumped has been apt to work back into the crank case, or oil work out of the crank case, both of which leakages are eliminated in the present invention.

SUMMARY OF THE INVENTION The reciprocating piston pump of the present invention includes a crank case, a crankshaft journalled therein, a plurality of crossheads slidably mounted at one side of the crank case in replaceable sleeves, and a connecting rod between each crosshead and the crankshaft. Each crosshead carries a piston rod on which is mounted a piston, and sealing means are provided between each rod and the crank case. A cylinder surrounds each piston with intake and outlet valves on each cylinder, and intake and outlet manifolds connect respectively the upstream side of the intake valves and the downstream side of the outlet valves.

Among the objects of the invention are to provide an improved liquid pump characterized by particular long life, ready serviceability, relatively low cost, and better performance. An improved oil system is provided, together with improved means for sealing dirt and liquid pumped from the crank case and preventing loss of oil from the crank case, and wherein the sealing means themselves act to supplement the oiling system. Replaceable crosshead sleeves are provided in the pump to facilitate repair. Readily operable means rigidly but releasably secure each piston to its rod, and the pump is adaptable to use with a double or a single bank of pumping cylinders. A final object is to provide an improved valve, piston, and cylinder construction.

THE DRAWINGS- FIG. 1 is a side elevational view, partially broken away in vertical cross section, of the pump of the invention in the double capacity of six cylinder version, the right hand side being largely broken away;

FIG. 2 is an end elevation of the pump of FIG. 1 showing the individual caps of the identical intake and exhaust valves;

FIGS. 3 and 4 are vertical cross sectional views of a crosshead, bellows and piston rod, and illustrate the oil flow thereabouts on the exhaust stroke and intake strokes respectively;

FIG. 5 is an enlarged sectional view illustrating the manner of releasably connecting each piston to its rod; and

FIG. 6 is substantially a horizontal cross sectional view taken on line VI-Vl of FIG. 1, but with portions of the connecting rods and crankshaft shown in elevation, and of a modification of the inventionwherein no pumping pistons and cylinders, crossheads, etc. are

present on the right hand side of the crank case but only a cover plate.

In the drawings the numeral 10 indicates generally a crank case having a top cover 12 and journalling in ball or roller bearings 14 a crankshaft 16 whose ends extend out of the case to be driven by a prime mover (not shown), such as an electric motor. In the embodiment of the invention illustrated, i.e., with three pumping cylinders on each side of the crank case, the crankshaft 16 is formed with three crank arms angularly separated 120 degrees, and each crank arm carries a connecting rod 18 extending to a crosshead 20 and pivotally connected thereto by a pin 22 surrounded by a bushing 24 (see FIGS. 3 and 4). Each crosshead 20 is guided in true linear movement by a sleeve 26 having a cylindrical flange 28 about its periphery and formed with a groove to receive a sealing O-ring 30.

Secured to each side of the crank case 10 is a pump head, shown generally at 32, and having a base flange 34, a middle flange 36 and an outer flange 38. The base flange and middle flange are integrally joined with a U- shaped section 40, and the middle flange 36 and outer flange 38 are integrally joined with an intake manifold or chamber 42 having a conduit connection opening The base flange 34 is formed, in the embodiment of the invention illustrated, with three circular openings placed in line horizontally to receive the crosshead sleeves 26, these openings being counter bored to receive and seal with the flanges 28 of each sleeve. Studs and nuts 46 secure the pump head 32 to the crank case 10. v

The middle flange 36 and outer flange 38 of the pump head 32 are formed with cylindrical openings in line with the crosshead sleeves 26 and each receives a cylinder 48 held against a shoulder 50 by a ported spacer ring 52 and an outlet valve plug 54. Each valve plug 54 has a spanner bar 56 extending over its outer end and studs and nuts secure the ends of each spanner bar to the outer flange 38 and tighten each cylinder assembly together. Thus, each valve plug and cylinder assembly can be individually serviced. Sealing O-rings 60 render each valve and cylinder assembly fluid-tight.

Each outlet valve plug 54 is formed with circumferentially spaced fingers 62 which engage the ported spacer 52, and this spacer is counter bored to receive a valve seat 64. The seat is engaged by a valve disc 66 having a short axial stud 68'on each side gripped by a conical spring 70 snapping into a counter bore on the inner surface of the valve plug. Each valve seat and disc can be accordingly turned over in the event of wear or corrosion. An outlet port 72 formed integrally with the outer flange 38 connects to the down stream side of the outlet valves through the openings of the fingers 62 of each outlet valve plug, and through manifolding openings in the flange 38.

The inlet valve plugs 74 are identical with the outlet valve plugs, and have identical fingers 62a, valve seats 64a, valve discs 66a, studs 68a, springs 70a, spanner bars 56a and stud nuts 580. However, a longitudinally shorter spacer 76 carries each valve seat 64a and each is received against a shoulder 78 formed in horizontally aligned bores in the outer flange 38 and connected by large ports 80 with the intake chamber 42. Sealing 0- rings 82 render the intake valve assemblies fluid tight. A port 84 connects via spaced fingers 62a the down stream side of each intake valve to its associated pumping cylinder.

Returning to the crossheads 20, each is formed with an integral piston rod 86 which extends to a piston 88 sliding in each cylinder 48. Each rod is rigidly and releasably connected to its piston as best seen in FIG. 5. The end of the piston rod is formed with a groove 90 having a beveled side 92, and the groove receives a diametrically split wedge ring 94 having one beveled surface engaging the beveled side 92 of groove 90. The wedge ring also has a beveled surface 96 engaging a complimentary bevel in the piston. The skirt of the piston is internally threaded and receives a nut 98 having a slotted sleeve-like extension 100 with a beveled end 102 engaging a complimentary bevel on wedge ring 94. Thus, when nut 98 is tightened bevels 102, 96, and 92 force the split halves of wedge ring 94 tightly into groove 90 and force the fingers of split extension 100 out against the piston to lock the piston 88 on rod 86.

The piston 88 is grooved to receive packing 104 and a nut 106 threaded to the outside of the piston skirt controls the pressure on the packing.

Positioned between each piston rod 86 and the outer end of each crosshead sleeve 26 is a flexible bellows 108 secured in sealing relation at each end by elastic lock rings 110. Accordingly, escape of oil from the crank case is prevented, as well as entry of outside dirt or liquid pumped into the crank case. A compression spring 112 surrounds the piston rod 86 bearing at one end on nut 98 to'prevent its loosening, and at its other end against elastic lock ring 110 and a shoulder 114 on the rod.

The invention provides an improved manner of lubricating the crossheads in their sleeves and also connecting rod pin 22, and this is achieved by providing a channel 116 and ,oil hole 118 in each sleeve 26- which catches oil thrown by the crankshaft 16 and dripping off the wall of the crank case 10. Oil holes 120 are provided in each crosshead 20, and hole 122 in each connecting rod 18 for passage of oil. Each connecting rod also has an oil groove 124 and an oil passage 126. During the reciprocating movement of each crosshead the bellows 108 acts as an oil pump and causes turbulence and splashing of the oil confined adjacent each crosshead. The resulting oil flows are shown in the pressure stroke of FIG. 3 and the suction stroke of FIG. 4.

FIG. 6 illustrates the modification of the invention wherein pumping cylinders extend to only one side of the crank case 10 and the pump has only half of the capacity of that shown in FIG. 1. In FIG. 6, a cover plate 128 closes the unused half of the crank case, and a spacer collar 130 is bolted around the crankshaft on each crank arm instead of a connecting rod. FIG. 6 fur ther shows another view of bushing 24 around pin 22, and the manner of locking each pin 22 to its crosshead 20.

Footer angles, 132 (FIG. 1.) provide for floor mounting of the pump and crank case assembly.

The invention employs anti-corrosion materials where needed throughout. Pumping cylinders and packing are readily replaced when worn, and all intake and exhaust valves can be readily checked and are interchangeable. Crosshead wear is kept to a minimum by the quality of its lubrication and the sleeves 26 can be replaced readily when desired. The result is a particularly long wearing and yet readily serviced pump.

In accord with the Patent Statutes the invention has been specifically illustrated and described. However, it will be understood that the invention is not to be specifically limited thereto, but that the scope of the invention is defined in the appended claims.

What is claimed is:

l. A reciprocating pump for liquids including a crank case, a crankshaft joumalled in the crank case, a plurality of crossheads slidably joumalled at one side of the crank case, a piston rod carried by each crosshead, a connecting rod between each crosshead and the crankshaft, sealing means between each piston rod and the crank case, a piston rigidly but removably secured on each piston rod, a cylinder surrounding each piston, an intake valve for each cylinder, an intake manifold connecting to the upstream side of each intake valve, an outlet valve for each cylinder, and an outlet manifold connecting to the downstream side of each outlet valve;

an individual sleeve for and slidably mounting each crosshead, and the sealing means between each piston rod and the crank case is a bellows secured at one end to the sleeve and at its other end to the pis ton rod; and

the sleeve being fonned with a channel to receive oil drippings from the inside of the crank case, the sleeve has an oil hole through it connected to the channel, and each crosshead and connecting rod have aligned oil holes periodically movable beneath the oil hole in the sleeve, a pin with surrounding bushing connects each crosshead to its connecting rod, and each crosshead has openings from the bushing towards the bellows whereby the bellows acts as a pump upon reciprocating movement of the crosshead to cause a continuous flow of oil around the pin, bushing, and between each crosshead and its sleeve.

2. A reciprocating pump for liquids including a crank case, a crankshaft joumalled in the crank case, a plurality of crossheads slidably joumalled at one side of the crank case, a piston rod carried by each crosshead, a connecting rod between each crosshead and the crank shaft, sealing means between each piston rod and the crank case, a piston rigidly but removably secured on each pistonrod, a cylinder surrounding each piston, an intake valve for each cylinder, an intake manifold connecting to the upstream side of each intake valve, an outlet valve for each cylinder, and an outlet manifold cognecting to the downstream side of each outlet valve; an

each said piston is rigidly but removably secured to its piston rod by means of a nut which is rotatable on the piston rod and screws into the piston skirt, each said piston rod having an annular groove therein with a beveled side thereon facing axially rearwardly, a diametrically split wedge ring with a surface complementary to said beveled side received in said groove with said surface and side being engaged, complementary means being provided on said wedge ring and the inner end of said nut to force part of said wedge ring against said piston by tightening said nut which also forces said wedge ring into engagement with said piston rod.

3. The combination defined in claim 9 wherein said complementary means including said wedge ring also having a second beveled surface facing axially rearwardly protruding radially of said groove, said nut having a split extension on its inner end beveled complementary to said second beveled surface and engaged therewith whereby tightening said nut forces said wedge ring into engagement with said piston rod and forces said extension out against said piston to lock said piston on its piston rod.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,817,663 Dated June 18 1974 Inventor-( William H. Zehner It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, Claim 3, line 1, "Claim 9" should be Claim 2 Signed and sealed this 8th day of October 1974.

(SEAL) Attest:

COY M. GIBSON JR. C. DANN fitesting Officer Commissloner of Patents USCOMM-DC 6037 6-P69 FORM PO-1050 (10-69) 1' u s, novznummr PRINTING OFFICE: I989 0-366-334 

1. A reciprocating pump for liquids including a crank case, a crankshaft journalled in the crank case, a plurality of crossheads slidably journalled at one side of the crank case, a piston rod carried by each crosshead, a connecting rod between each crosshead and the crankshaft, sealing means between each piston rod and the crank case, a piston rigidly but removably secured on each piston rod, a cylinder surrounding eaCh piston, an intake valve for each cylinder, an intake manifold connecting to the upstream side of each intake valve, an outlet valve for each cylinder, and an outlet manifold connecting to the downstream side of each outlet valve; an individual sleeve for and slidably mounting each crosshead, and the sealing means between each piston rod and the crank case is a bellows secured at one end to the sleeve and at its other end to the piston rod; and the sleeve being formed with a channel to receive oil drippings from the inside of the crank case, the sleeve has an oil hole through it connected to the channel, and each crosshead and connecting rod have aligned oil holes periodically movable beneath the oil hole in the sleeve, a pin with surrounding bushing connects each crosshead to its connecting rod, and each crosshead has openings from the bushing towards the bellows whereby the bellows acts as a pump upon reciprocating movement of the crosshead to cause a continuous flow of oil around the pin, bushing, and between each crosshead and its sleeve.
 2. A reciprocating pump for liquids including a crank case, a crankshaft journalled in the crank case, a plurality of crossheads slidably journalled at one side of the crank case, a piston rod carried by each crosshead, a connecting rod between each crosshead and the crank shaft, sealing means between each piston rod and the crank case, a piston rigidly but removably secured on each piston rod, a cylinder surrounding each piston, an intake valve for each cylinder, an intake manifold connecting to the upstream side of each intake valve, an outlet valve for each cylinder, and an outlet manifold connecting to the downstream side of each outlet valve; and each said piston is rigidly but removably secured to its piston rod by means of a nut which is rotatable on the piston rod and screws into the piston skirt, each said piston rod having an annular groove therein with a beveled side thereon facing axially rearwardly, a diametrically split wedge ring with a surface complementary to said beveled side received in said groove with said surface and side being engaged, complementary means being provided on said wedge ring and the inner end of said nut to force part of said wedge ring against said piston by tightening said nut which also forces said wedge ring into engagement with said piston rod.
 3. The combination defined in claim 9 wherein said complementary means including said wedge ring also having a second beveled surface facing axially rearwardly protruding radially of said groove, said nut having a split extension on its inner end beveled complementary to said second beveled surface and engaged therewith whereby tightening said nut forces said wedge ring into engagement with said piston rod and forces said extension out against said piston to lock said piston on its piston rod. 